Inflation: What It Is, Types, Causes, How It's Measured, and Why It Matters

Inflation is the sustained increase in the general price level of goods and services over time. When inflation occurs, each unit of currency buys fewer items than before — meaning your money loses purchasing power.

Inflation is not always a bad thing. Most economists agree that a moderate inflation rate of 2-3% per year is healthy for an economy because it encourages spending and investment rather than hoarding cash. However, when inflation spirals out of control, it can devastate economies and livelihoods.

"Inflation is taxation without legislation." — Milton Friedman, Nobel Laureate in Economics

Imagine in January 2022, a kg of rice cost $1.00. By December 2022, the same rice costs $1.10. That 10-cent increase means you now need more money to buy the same product. Multiply that across thousands of goods and services, and you have inflation.

Now think bigger: if a family's monthly grocery bill was $500 last year and the inflation rate is 8%, that same basket of groceries now costs $540 — an extra $40 per month without buying anything additional.

Inflation doesn't happen randomly. Several economic forces drive prices upward:

1. Excess Money Supply

When too much money circulates in the economy relative to the goods available, prices rise. If the central bank prints excessive amounts of currency, each unit of money becomes worth less. Zimbabwe's hyperinflation in 2008 reached 79.6 billion percent — a textbook example of what happens when money supply spirals out of control.

2. Government Spending

Large government projects and spending programs inject money into the economy. While this stimulates growth, excessive government spending — especially when funded by borrowing — can push prices up.

3. Credit Expansion

When banks make it easy to borrow money with low interest rates, consumers and businesses spend more. This increased demand, without a matching increase in supply, drives prices higher.

4. Production Decline

When production of goods falls — due to natural disasters, supply chain disruptions, or other shocks — the reduced supply against steady demand pushes prices up. The COVID-19 pandemic caused significant production disruptions worldwide, contributing to the inflation surge of 2021-2022.

5. Defaulted Loans

When a large volume of loans go unpaid, banks have less capital to lend. This can destabilize the financial system and indirectly contribute to inflationary pressures. According to Bangladesh Bank, non-performing loans exceeded 1.3 trillion taka by 2023.

6. Population Growth

Rapid population growth increases demand for food, housing, and services. If production doesn't keep pace, prices inevitably rise.

7. Political Instability

Political uncertainty disrupts economic activity, scares away investment, and can lead to excessive wage increases and hoarding — all of which fuel inflation.

1. Demand-Pull Inflation

Occurs when aggregate demand exceeds aggregate supply. Too many dollars chasing too few goods. This is the most common type during economic booms.

2. Cost-Push Inflation

Occurs when production costs rise — raw materials, wages, energy — forcing businesses to raise prices. The 2022 oil price spike following Russia's invasion of Ukraine is a classic example of cost-push inflation.

3. Built-In Inflation

Also called the wage-price spiral. When prices rise, workers demand higher wages. Higher wages increase production costs, which leads to even higher prices — creating a self-reinforcing cycle.

4. Imported Inflation

When the cost of imported goods rises — due to currency depreciation or global price increases — domestic prices follow. Countries heavily dependent on imports are especially vulnerable.

5. Monetary Inflation

When the central bank increases the money supply faster than the economy grows. More money in circulation means each unit is worth less, directly causing prices to rise.

Two primary indices are used to measure inflation:

1. Wholesale Price Index (WPI)

Tracks price changes at the wholesale (bulk) level — before goods reach consumers. It measures prices between businesses and is often used in India and some developing countries.

2. Consumer Price Index (CPI)

Tracks price changes of a basket of goods and services that a typical household buys. The CPI is the most widely used inflation measure globally. In the U.S., the Bureau of Labor Statistics publishes CPI data monthly.

The Inflation Rate Formula

Inflation Rate = ((Current Year CPI - Previous Year CPI) / Previous Year CPI) x 100

For example, if the CPI was 300 last year and 315 this year:

Inflation Rate = ((315 - 300) / 300) x 100 = 5%

• Stimulates economic growth — Mild inflation encourages spending rather than saving, boosting economic activity
• Benefits wages — Nominal wages tend to rise with inflation, and wage increases improve worker morale
• Increases asset values — Property and stock prices generally rise during moderate inflation, benefiting investors
• Reduces real debt burden — Borrowers benefit because they repay loans with money that is worth less than when they borrowed it

• Erodes purchasing power — People can buy less with the same amount of money, especially hard on fixed-income households
• Creates economic uncertainty — Businesses struggle to plan and invest when prices are unpredictable
• Hurts savers — Savings lose real value if interest rates don't keep up with inflation
• Increases cost of living — Essential goods become more expensive, disproportionately affecting the poor
• Can trigger unemployment — If businesses can't pass on costs, they may cut jobs to maintain profitability

Economists generally agree that mild inflation (2-3%) is the lubricant of economic growth. It keeps money circulating and encourages investment. But when inflation exceeds 5-10%, the negative effects start to dominate.

In Bangladesh, inflation has been a persistent concern. Rising food prices, currency depreciation, and global commodity price increases have pushed inflation rates higher. The central bank has responded by raising interest rates and tightening monetary policy — the standard tools for combating inflation.

"Inflation is always and everywhere a monetary phenomenon." — Milton Friedman

Inflation is an inevitable part of any growing economy. While moderate inflation can be healthy, excessive inflation destroys purchasing power, creates uncertainty, and widens inequality. Understanding its causes, types, and measurement helps individuals and policymakers make better financial decisions.

For the average person, the key takeaway is this: inflation means your money buys less over time. The best defense is to invest wisely, stay informed, and understand how economic policies affect the prices you pay every day.